1. Field of the Invention
The present invention relates generally to an integrated circuit structure including a fuse, and a method thereof, and more specifically to an integrated circuit structure including a fuse, and a method thereof, which applies a dummy right above the fuse.
2. Description of the Prior Art
As semiconductor processes become smaller and more complex, semiconductor components are more easily influenced by impurities. If a single metal link, a diode, or a MOS is broken down, the whole chip will be unusable. To treat this problem, fuses can be selectively blown to increase the yield of IC manufacturing.
Fused circuits are redundant circuits of an IC. When defects are found in a circuit, fuses can be selectively blown for repairing or replacing defective circuits. In addition, fuses provide the function of programming circuits for various customized functions. Fuses are classified into two categories based on their operation: thermal fuse and electrical fuse. Thermal fuses can be cut by lasers and linked by laser repair. An electrical fuse utilizes electro-migration both for forming open circuits and for repairing. The electrical fuse for semiconductor devices may be classified into categories of poly electrical fuse, MOS capacitor anti-fuse, diffusion fuse, contact electrical fuse, and contact anti-fuse.
In the conventional art, a protection layer is formed on a fuse for two purposes. The protection layer insulates the fuse from the external environment and also protects the fuse from corrosion. Furthermore, if a laser repair is performed, the protection layer insulates the heat absorbed by the fuse to thereby prevent it from escaping and achieve an effective burnout. Unfortunately, the thickness of the formed protection layer is difficult to be controlled precisely. Therefore, how to fabricate a fuse having an accurate predetermined thickness has become an important task in the field.